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<a class="jxr_linenumber" name="1" href="#1">1</a>   <em class="jxr_comment">/*</em>
<a class="jxr_linenumber" name="2" href="#2">2</a>   <em class="jxr_comment"> * Licensed to the Apache Software Foundation (ASF) under one or more</em>
<a class="jxr_linenumber" name="3" href="#3">3</a>   <em class="jxr_comment"> * contributor license agreements.  See the NOTICE file distributed with</em>
<a class="jxr_linenumber" name="4" href="#4">4</a>   <em class="jxr_comment"> * this work for additional information regarding copyright ownership.</em>
<a class="jxr_linenumber" name="5" href="#5">5</a>   <em class="jxr_comment"> * The ASF licenses this file to You under the Apache License, Version 2.0</em>
<a class="jxr_linenumber" name="6" href="#6">6</a>   <em class="jxr_comment"> * (the "License"); you may not use this file except in compliance with</em>
<a class="jxr_linenumber" name="7" href="#7">7</a>   <em class="jxr_comment"> * the License.  You may obtain a copy of the License at</em>
<a class="jxr_linenumber" name="8" href="#8">8</a>   <em class="jxr_comment"> *</em>
<a class="jxr_linenumber" name="9" href="#9">9</a>   <em class="jxr_comment"> *     <a href="http://www.apache.org/licenses/LICENSE-2.0" target="alexandria_uri">http://www.apache.org/licenses/LICENSE-2.0</a></em>
<a class="jxr_linenumber" name="10" href="#10">10</a>  <em class="jxr_comment"> *</em>
<a class="jxr_linenumber" name="11" href="#11">11</a>  <em class="jxr_comment"> * Unless required by applicable law or agreed to in writing, software</em>
<a class="jxr_linenumber" name="12" href="#12">12</a>  <em class="jxr_comment"> * distributed under the License is distributed on an "AS IS" BASIS,</em>
<a class="jxr_linenumber" name="13" href="#13">13</a>  <em class="jxr_comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</em>
<a class="jxr_linenumber" name="14" href="#14">14</a>  <em class="jxr_comment"> * See the License for the specific language governing permissions and</em>
<a class="jxr_linenumber" name="15" href="#15">15</a>  <em class="jxr_comment"> * limitations under the License.</em>
<a class="jxr_linenumber" name="16" href="#16">16</a>  <em class="jxr_comment"> */</em>
<a class="jxr_linenumber" name="17" href="#17">17</a>  <strong class="jxr_keyword">package</strong> org.apache.commons.configuration.tree;
<a class="jxr_linenumber" name="18" href="#18">18</a>  
<a class="jxr_linenumber" name="19" href="#19">19</a>  
<a class="jxr_linenumber" name="20" href="#20">20</a>  <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="21" href="#21">21</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a class="jxr_linenumber" name="22" href="#22">22</a>  <em class="jxr_javadoccomment"> * A concrete combiner implementation that is able to construct an override</em>
<a class="jxr_linenumber" name="23" href="#23">23</a>  <em class="jxr_javadoccomment"> * combination.</em>
<a class="jxr_linenumber" name="24" href="#24">24</a>  <em class="jxr_javadoccomment"> * &lt;/p&gt;</em>
<a class="jxr_linenumber" name="25" href="#25">25</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a class="jxr_linenumber" name="26" href="#26">26</a>  <em class="jxr_javadoccomment"> * An &lt;em&gt;override combination&lt;/em&gt; means that nodes in the first node</em>
<a class="jxr_linenumber" name="27" href="#27">27</a>  <em class="jxr_javadoccomment"> * structure take precedence over nodes in the second, or - in other words -</em>
<a class="jxr_linenumber" name="28" href="#28">28</a>  <em class="jxr_javadoccomment"> * nodes of the second structure are only added to the resulting structure if</em>
<a class="jxr_linenumber" name="29" href="#29">29</a>  <em class="jxr_javadoccomment"> * they do not occur in the first one. This is especially suitable for dealing</em>
<a class="jxr_linenumber" name="30" href="#30">30</a>  <em class="jxr_javadoccomment"> * with the properties of configurations that are defined in an</em>
<a class="jxr_linenumber" name="31" href="#31">31</a>  <em class="jxr_javadoccomment"> * {@code override} section of a configuration definition file (hence the</em>
<a class="jxr_linenumber" name="32" href="#32">32</a>  <em class="jxr_javadoccomment"> * name).</em>
<a class="jxr_linenumber" name="33" href="#33">33</a>  <em class="jxr_javadoccomment"> * &lt;/p&gt;</em>
<a class="jxr_linenumber" name="34" href="#34">34</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a class="jxr_linenumber" name="35" href="#35">35</a>  <em class="jxr_javadoccomment"> * This combiner will iterate over the second node hierarchy and find all nodes</em>
<a class="jxr_linenumber" name="36" href="#36">36</a>  <em class="jxr_javadoccomment"> * that are not contained in the first hierarchy; these are added to the result.</em>
<a class="jxr_linenumber" name="37" href="#37">37</a>  <em class="jxr_javadoccomment"> * If a node can be found in both structures, it is checked whether a</em>
<a class="jxr_linenumber" name="38" href="#38">38</a>  <em class="jxr_javadoccomment"> * combination (in a recursive way) can be constructed for the two, which will</em>
<a class="jxr_linenumber" name="39" href="#39">39</a>  <em class="jxr_javadoccomment"> * then be added. Per default, nodes are combined, which occur only once in both</em>
<a class="jxr_linenumber" name="40" href="#40">40</a>  <em class="jxr_javadoccomment"> * structures. This test is implemented in the {@code canCombine()}</em>
<a class="jxr_linenumber" name="41" href="#41">41</a>  <em class="jxr_javadoccomment"> * method.</em>
<a class="jxr_linenumber" name="42" href="#42">42</a>  <em class="jxr_javadoccomment"> * &lt;/p&gt;</em>
<a class="jxr_linenumber" name="43" href="#43">43</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a class="jxr_linenumber" name="44" href="#44">44</a>  <em class="jxr_javadoccomment"> * As is true for the {@link UnionCombiner}, for this combiner</em>
<a class="jxr_linenumber" name="45" href="#45">45</a>  <em class="jxr_javadoccomment"> * list nodes are important. The {@code addListNode()} can be called to</em>
<a class="jxr_linenumber" name="46" href="#46">46</a>  <em class="jxr_javadoccomment"> * declare certain nodes as list nodes. This has the effect that these nodes</em>
<a class="jxr_linenumber" name="47" href="#47">47</a>  <em class="jxr_javadoccomment"> * will never be combined.</em>
<a class="jxr_linenumber" name="48" href="#48">48</a>  <em class="jxr_javadoccomment"> * &lt;/p&gt;</em>
<a class="jxr_linenumber" name="49" href="#49">49</a>  <em class="jxr_javadoccomment"> *</em>
<a class="jxr_linenumber" name="50" href="#50">50</a>  <em class="jxr_javadoccomment"> * @author &lt;a</em>
<a class="jxr_linenumber" name="51" href="#51">51</a>  <em class="jxr_javadoccomment"> * href="<a href="http://commons.apache.org/configuration/team-list.html" target="alexandria_uri">http://commons.apache.org/configuration/team-list.html</a>"&gt;Commons</em>
<a class="jxr_linenumber" name="52" href="#52">52</a>  <em class="jxr_javadoccomment"> * Configuration team&lt;/a&gt;</em>
<a class="jxr_linenumber" name="53" href="#53">53</a>  <em class="jxr_javadoccomment"> * @version $Id: OverrideCombiner.java 1301991 2012-03-17 20:18:02Z sebb $</em>
<a class="jxr_linenumber" name="54" href="#54">54</a>  <em class="jxr_javadoccomment"> * @since 1.3</em>
<a class="jxr_linenumber" name="55" href="#55">55</a>  <em class="jxr_javadoccomment"> */</em>
<a class="jxr_linenumber" name="56" href="#56">56</a>  <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../org/apache/commons/configuration/tree/OverrideCombiner.html">OverrideCombiner</a> <strong class="jxr_keyword">extends</strong> <a href="../../../../../org/apache/commons/configuration/tree/NodeCombiner.html">NodeCombiner</a>
<a class="jxr_linenumber" name="57" href="#57">57</a>  {
<a class="jxr_linenumber" name="58" href="#58">58</a>      <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="59" href="#59">59</a>  <em class="jxr_javadoccomment">     * Constructs an override combination for the passed in node structures.</em>
<a class="jxr_linenumber" name="60" href="#60">60</a>  <em class="jxr_javadoccomment">     *</em>
<a class="jxr_linenumber" name="61" href="#61">61</a>  <em class="jxr_javadoccomment">     * @param node1 the first node</em>
<a class="jxr_linenumber" name="62" href="#62">62</a>  <em class="jxr_javadoccomment">     * @param node2 the second node</em>
<a class="jxr_linenumber" name="63" href="#63">63</a>  <em class="jxr_javadoccomment">     * @return the resulting combined node structure</em>
<a class="jxr_linenumber" name="64" href="#64">64</a>  <em class="jxr_javadoccomment">     */</em>
<a class="jxr_linenumber" name="65" href="#65">65</a>      @Override
<a class="jxr_linenumber" name="66" href="#66">66</a>      <strong class="jxr_keyword">public</strong> <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> combine(<a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node1,
<a class="jxr_linenumber" name="67" href="#67">67</a>              <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node2)
<a class="jxr_linenumber" name="68" href="#68">68</a>      {
<a class="jxr_linenumber" name="69" href="#69">69</a>          <a href="../../../../../org/apache/commons/configuration/tree/ViewNode.html">ViewNode</a> result = createViewNode();
<a class="jxr_linenumber" name="70" href="#70">70</a>          result.setName(node1.getName());
<a class="jxr_linenumber" name="71" href="#71">71</a>  
<a class="jxr_linenumber" name="72" href="#72">72</a>          <em class="jxr_comment">// Process nodes from the first structure, which override the second</em>
<a class="jxr_linenumber" name="73" href="#73">73</a>          <strong class="jxr_keyword">for</strong> (ConfigurationNode child : node1.getChildren())
<a class="jxr_linenumber" name="74" href="#74">74</a>          {
<a class="jxr_linenumber" name="75" href="#75">75</a>              <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> child2 = canCombine(node1, node2, child);
<a class="jxr_linenumber" name="76" href="#76">76</a>              <strong class="jxr_keyword">if</strong> (child2 != <strong class="jxr_keyword">null</strong>)
<a class="jxr_linenumber" name="77" href="#77">77</a>              {
<a class="jxr_linenumber" name="78" href="#78">78</a>                  result.addChild(combine(child, child2));
<a class="jxr_linenumber" name="79" href="#79">79</a>              }
<a class="jxr_linenumber" name="80" href="#80">80</a>              <strong class="jxr_keyword">else</strong>
<a class="jxr_linenumber" name="81" href="#81">81</a>              {
<a class="jxr_linenumber" name="82" href="#82">82</a>                  result.addChild(child);
<a class="jxr_linenumber" name="83" href="#83">83</a>              }
<a class="jxr_linenumber" name="84" href="#84">84</a>          }
<a class="jxr_linenumber" name="85" href="#85">85</a>  
<a class="jxr_linenumber" name="86" href="#86">86</a>          <em class="jxr_comment">// Process nodes from the second structure, which are not contained</em>
<a class="jxr_linenumber" name="87" href="#87">87</a>          <em class="jxr_comment">// in the first structure</em>
<a class="jxr_linenumber" name="88" href="#88">88</a>          <strong class="jxr_keyword">for</strong> (ConfigurationNode child : node2.getChildren())
<a class="jxr_linenumber" name="89" href="#89">89</a>          {
<a class="jxr_linenumber" name="90" href="#90">90</a>              <strong class="jxr_keyword">if</strong> (node1.getChildrenCount(child.getName()) &lt; 1)
<a class="jxr_linenumber" name="91" href="#91">91</a>              {
<a class="jxr_linenumber" name="92" href="#92">92</a>                  result.addChild(child);
<a class="jxr_linenumber" name="93" href="#93">93</a>              }
<a class="jxr_linenumber" name="94" href="#94">94</a>          }
<a class="jxr_linenumber" name="95" href="#95">95</a>  
<a class="jxr_linenumber" name="96" href="#96">96</a>          <em class="jxr_comment">// Handle attributes and value</em>
<a class="jxr_linenumber" name="97" href="#97">97</a>          addAttributes(result, node1, node2);
<a class="jxr_linenumber" name="98" href="#98">98</a>          result.setValue((node1.getValue() != <strong class="jxr_keyword">null</strong>) ? node1.getValue() : node2
<a class="jxr_linenumber" name="99" href="#99">99</a>                  .getValue());
<a class="jxr_linenumber" name="100" href="#100">100</a> 
<a class="jxr_linenumber" name="101" href="#101">101</a>         <strong class="jxr_keyword">return</strong> result;
<a class="jxr_linenumber" name="102" href="#102">102</a>     }
<a class="jxr_linenumber" name="103" href="#103">103</a> 
<a class="jxr_linenumber" name="104" href="#104">104</a>     <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="105" href="#105">105</a> <em class="jxr_javadoccomment">     * Handles the attributes during a combination process. First all attributes</em>
<a class="jxr_linenumber" name="106" href="#106">106</a> <em class="jxr_javadoccomment">     * of the first node will be added to the result. Then all attributes of the</em>
<a class="jxr_linenumber" name="107" href="#107">107</a> <em class="jxr_javadoccomment">     * second node, which are not contained in the first node, will also be</em>
<a class="jxr_linenumber" name="108" href="#108">108</a> <em class="jxr_javadoccomment">     * added.</em>
<a class="jxr_linenumber" name="109" href="#109">109</a> <em class="jxr_javadoccomment">     *</em>
<a class="jxr_linenumber" name="110" href="#110">110</a> <em class="jxr_javadoccomment">     * @param result the resulting node</em>
<a class="jxr_linenumber" name="111" href="#111">111</a> <em class="jxr_javadoccomment">     * @param node1 the first node</em>
<a class="jxr_linenumber" name="112" href="#112">112</a> <em class="jxr_javadoccomment">     * @param node2 the second node</em>
<a class="jxr_linenumber" name="113" href="#113">113</a> <em class="jxr_javadoccomment">     */</em>
<a class="jxr_linenumber" name="114" href="#114">114</a>     <strong class="jxr_keyword">protected</strong> <strong class="jxr_keyword">void</strong> addAttributes(<a href="../../../../../org/apache/commons/configuration/tree/ViewNode.html">ViewNode</a> result, <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node1,
<a class="jxr_linenumber" name="115" href="#115">115</a>             <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node2)
<a class="jxr_linenumber" name="116" href="#116">116</a>     {
<a class="jxr_linenumber" name="117" href="#117">117</a>         result.appendAttributes(node1);
<a class="jxr_linenumber" name="118" href="#118">118</a>         <strong class="jxr_keyword">for</strong> (ConfigurationNode attr : node2.getAttributes())
<a class="jxr_linenumber" name="119" href="#119">119</a>         {
<a class="jxr_linenumber" name="120" href="#120">120</a>             <strong class="jxr_keyword">if</strong> (node1.getAttributeCount(attr.getName()) == 0)
<a class="jxr_linenumber" name="121" href="#121">121</a>             {
<a class="jxr_linenumber" name="122" href="#122">122</a>                 result.addAttribute(attr);
<a class="jxr_linenumber" name="123" href="#123">123</a>             }
<a class="jxr_linenumber" name="124" href="#124">124</a>         }
<a class="jxr_linenumber" name="125" href="#125">125</a>     }
<a class="jxr_linenumber" name="126" href="#126">126</a> 
<a class="jxr_linenumber" name="127" href="#127">127</a>     <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="128" href="#128">128</a> <em class="jxr_javadoccomment">     * Tests if a child node of the second node can be combined with the given</em>
<a class="jxr_linenumber" name="129" href="#129">129</a> <em class="jxr_javadoccomment">     * child node of the first node. If this is the case, the corresponding node</em>
<a class="jxr_linenumber" name="130" href="#130">130</a> <em class="jxr_javadoccomment">     * will be returned, otherwise &lt;b&gt;null&lt;/b&gt;. This implementation checks</em>
<a class="jxr_linenumber" name="131" href="#131">131</a> <em class="jxr_javadoccomment">     * whether the child node occurs only once in both hierarchies and is no</em>
<a class="jxr_linenumber" name="132" href="#132">132</a> <em class="jxr_javadoccomment">     * known list node.</em>
<a class="jxr_linenumber" name="133" href="#133">133</a> <em class="jxr_javadoccomment">     *</em>
<a class="jxr_linenumber" name="134" href="#134">134</a> <em class="jxr_javadoccomment">     * @param node1 the first node</em>
<a class="jxr_linenumber" name="135" href="#135">135</a> <em class="jxr_javadoccomment">     * @param node2 the second node</em>
<a class="jxr_linenumber" name="136" href="#136">136</a> <em class="jxr_javadoccomment">     * @param child the child node (of the first node)</em>
<a class="jxr_linenumber" name="137" href="#137">137</a> <em class="jxr_javadoccomment">     * @return a child of the second node, with which a combination is possible</em>
<a class="jxr_linenumber" name="138" href="#138">138</a> <em class="jxr_javadoccomment">     */</em>
<a class="jxr_linenumber" name="139" href="#139">139</a>     <strong class="jxr_keyword">protected</strong> <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> canCombine(<a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node1,
<a class="jxr_linenumber" name="140" href="#140">140</a>             <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> node2, <a href="../../../../../org/apache/commons/configuration/tree/ConfigurationNode.html">ConfigurationNode</a> child)
<a class="jxr_linenumber" name="141" href="#141">141</a>     {
<a class="jxr_linenumber" name="142" href="#142">142</a>         <strong class="jxr_keyword">if</strong> (node2.getChildrenCount(child.getName()) == 1
<a class="jxr_linenumber" name="143" href="#143">143</a>                 &amp;&amp; node1.getChildrenCount(child.getName()) == 1
<a class="jxr_linenumber" name="144" href="#144">144</a>                 &amp;&amp; !isListNode(child))
<a class="jxr_linenumber" name="145" href="#145">145</a>         {
<a class="jxr_linenumber" name="146" href="#146">146</a>             <strong class="jxr_keyword">return</strong> node2.getChildren(child.getName()).get(0);
<a class="jxr_linenumber" name="147" href="#147">147</a>         }
<a class="jxr_linenumber" name="148" href="#148">148</a>         <strong class="jxr_keyword">else</strong>
<a class="jxr_linenumber" name="149" href="#149">149</a>         {
<a class="jxr_linenumber" name="150" href="#150">150</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">null</strong>;
<a class="jxr_linenumber" name="151" href="#151">151</a>         }
<a class="jxr_linenumber" name="152" href="#152">152</a>     }
<a class="jxr_linenumber" name="153" href="#153">153</a> }
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